Bio-mass and viability
Capacitance sensor technology measures equally well adherent or suspension type of mammalian cells. The bio-mass sensor system senses total capacitance measured in pico Farad. Viable Cell Density (VCD) system monitors the volume of live cells. The principle is expressed in permittivity as the system is capable of detecting the response of cells with intact membranes. Cell fragments, particles and gas bubbles are not measured. Small micro-organism's like bacteria is not the best to measure with this technology.
Capacitance biomass Re-Usable-Sensors (RUS) are available in PG 13,5 x 120, 225, 325 mm length. The sensor communicates on-line and only through the specific pre-amplifier to a computer/display and various output for external devices. The RUS, pre-amplifier and display is available from:
Measured parameters on mammalian cell (app 18 µm size) are: Viable Cell Density, Conductivity, Fc, indicating average cell size, Alpha, indicating cell size distribution, DeltaEpsilon, multi frequency cell density.
Bio-mass test performed in CellTank
Under Download/References on www.perfusecell.com you may have noticed that as much as 200 pF/cm has been observed in CellTank #34-0150 cultivating mammalian CHO suspension cell lines. In general the conversion ration then was:
- Approximately 1 pF/cm is equivalent to 1x10E+06/ml cells for suspension cells
- Approximately 10 pF/cm is equivalent to 1x10E+06/ml cells for adherent cells
Measured at 37°C temperature. We recommend reading the KTH March 2012 presentation found under http://perfusecell.com/download